Pharmacokinetics of dehydroepiandrosterone and its metabolites after long-term oral dehydroepiandrosterone treatment in postmenopausal women.

OBJECTIVE: Some postmenopausal women use over-the-counter dehydroepiandrosterone because of its purported beneficial effects. Although without major inherent androgenic activity, it is metabolized to potent androgens and estrogens. We investigated the pharmacokinetics of dehydroepiandrosterone and its relevant metabolites after prolonged treatment of postmenopausal women with 25 mg/d of dehydroepiandrosterone. METHODS: Twenty healthy postmenopausal women were randomized to either 25 mg/d of dehydroepiandrosterone or placebo for 6 months. Frequent blood samples were obtained over 24 hours on day 1 and after 3 and 6 months. RESULTS: Mean baseline androgen levels at day 1 and month 3 in the treated group (seven evaluable women) were the following: dehydroepiandrosterone, 1.82 and 3.56 ng/mL; dehydroepiandrosterone sulfate, 0.96 and 3.37 microg/mL; 5-androstene-3beta,17beta-diol, 0.32 and 0.66 ng/mL; androstenedione, 0.50 and 0.86 ng/mL; testosterone, 17.9 and 28.7 ng/dL; dihydrotestosterone, 6.91 and 17.4 ng/dL; and 3alpha-androstanediol glucuronide, 2.66 and 10.7 ng/mL, respectively; these increases were significant. Small changes (-6% to 16%) were observed from month 3 to month 6. Nonsignificant increases were observed in baseline estrone and estradiol levels and in Cmax and AUC0-24h values for the androgens and estrogens from day 1 to months 3 and 6 of treatment. Sex hormone-binding globulin levels were unchanged, but free testosterone increased significantly from day 1 to month 3. Baseline hormone levels did not increase in the placebo group (six evaluable women). Changes in baseline values over time differed significantly between the groups for all hormones except estrone and estradiol. CONCLUSIONS: In postmenopausal women treated orally with a commonly available dose of dehydroepiandrosterone, the daily exposure (AUC) of dehydroepiandrosterone and its principal androgenic metabolites was found to be similar during 6 months of treatment despite increased serum baseline concentrations of these androgens.

Influence of DHEA administration on 24-hour cortisol concentrations.

DHEA is marketed and readily available as a daily nutritional supplement to counteract the effects of aging. The effect of DHEA administration on 24-hour plasma cortisol profiles has not been investigated. In this single-blind placebo-controlled crossover study, the effect of DHEA administration on cortisol concentrations was evaluated in healthy older women and men. Once each morning, subjects took either placebo (Days 1 to 7, and 23 to 29) or oral DHEA 200 mg (Days 8 to 22: doses 1 to 15). Twenty-four hour DHEA and cortisol concentrations were measured on Day 1 (placebo), Day 8 (DHEA dose 1), Day 15 (DHEA dose 8), Day 22 (DHEA dose 15), and Day 29 (placebo washout dose 7). DHEA administration resulted in a decrease in plasma cortisol concentrations (mean, peak, and/or AUC) in healthy older women and men. The cortisol-lowering effect of DHEA was more pronounced in women than in men in our study; pairwise differences in concentrations between days showed that relative to Day 1, cortisol was lower on Days 15, 22, and 29 in women (p = 0.0001) and on Day 15 in men (p = 0.002). The mechanism by which DHEA lowers plasma cortisol concentrations merits further investigation.